Large-scale next-generation networked systems like smart grids and vehicular networks facilitate extensive automation and autonomy through real-time communication of sensitive messages. Digital signatures are vital for such applications since they offer scalable broadcast authentication with non-repudiation. Yet, even conventional secure signatures (e.g., ECDSA, RSA) introduce significant cryptographic delays that can disrupt the safety of such delay-aware systems. With the rise of quantum computers breaking conventional intractability problems, these traditional cryptosystems must be replaced with post-quantum (PQ) secure ones. However, PQ-secure signatures are significantly costlier than their conventional counterparts, vastly exacerbating delay hurdles for real-time applications. We propose a new signature called Time Valid Probabilistic Data Structure HORS (TVPD-HORS) that achieves significantly lower end-to-end delay with a tunable PQ-security for real-time applications. We harness special probabilistic data structures as an efficient one-way function at the heart of our novelty, thereby vastly fastening HORS as a primitive for NIST PQ cryptography standards. TVPD-HORS permits tunable and fast processing for varying input sizes via One-hash Bloom Filter, excelling in time valid cases, wherein authentication with shorter security parameters is used for short-lived yet safety-critical messages. We show that TVPD-HORS verification is 2.7x and 5x faster than HORS in high-security and time valid settings, respectively. TVPD-HORS key generation is also faster, with a similar signing speed to HORS. Moreover, TVPD-HORS can increase the speed of HORS variants over a magnitude of time. These features make TVPD-HORS an ideal primitive to raise high-speed time valid versions of PQ-safe standards like XMSS and SPHINCS+, paving the way for real-time authentication of next-generation networks.

翻译：智能电网与车联网等大规模下一代网络系统通过敏感消息的实时通信，实现了广泛的自动化与自主化。数字签名对此类应用至关重要，因其可提供具备不可否认性的可扩展广播认证。然而，即使是传统安全签名（如ECDSA、RSA）也会引入显著的密码学延迟，可能破坏这类延迟敏感系统的安全性。随着量子计算机突破传统难解问题的兴起，这些传统密码系统必须被后量子（PQ）安全的方案所取代。但PQ安全签名的计算成本远高于传统方案，极大加剧了实时应用的延迟障碍。我们提出了一种名为时间有效概率数据结构HORS（TVPD-HORS）的新型签名方案，能够以可调的后量子安全级别为实时应用实现显著降低的端到端延迟。我们创新性地采用特殊概率数据结构作为高效单向函数的核心机制，从而大幅加速了作为NIST后量子密码标准的HORS原语。TVPD-HORS通过单哈希布隆过滤器实现对不同输入尺寸的可调快速处理，在时间有效场景中表现卓越——该场景下对短寿命但安全关键的消息采用较短安全参数的认证。实验表明，在高安全性和时间有效两种设置下，TVPD-HORS的验证速度分别比HORS快2.7倍和5倍。其密钥生成速度更快，签名速度与HORS相当。此外，TVPD-HORS可将HORS变体的速度提升一个数量级以上。这些特性使TVPD-HORS成为构建XMSS和SPHINCS+等PQ安全标准的高速时间有效版本的理想原语，为下一代网络的实时认证开辟了道路。